Process of dispersing bodies in water



- f lPnentefDec. 7,1926.- f'

' Nrrao sfr-A n hun' nahen rnn'r'r, moor-romand or noemen, serre. Y-

Elio drawing.

etable, or mineral origin, since the practice orl the process does not dep spersed in particlesoi such neness be ot the -character itl end upon 'the l@ selection -ot any particular dispersing agent,

unless the resultant productie to Ypossess certain predetermindd characteristics. A .il have discovered that it the body to be dispersed, unless 'already in a tacky more or 2li less plastic condition, is broughtA to this con-v ditionI by a heating or chilling1 medium, all at a temerature above the freezing point and not acre the boiling point ot water, it lrnay be caused to absorb a certain amount of Watenu'lhe amount oz? Water so absorbed varies with the absorption capacity ot the e particular-xl material to be dispersed, but orf' inarilythe amount up to the saturation point oi the body ranges @il ot the Weight ot the material. litter the water is thus absorbed by and dispersed throughout the mass et the material, l now -mix therewith a colloidal dispersing agent, and also Water in graduated amounts until a changein phase occurs and the material dispersas in a continuous V4aqueous medium.

Alter considering the phenomena occurn ring'orresulting'trom the various steps ot the process, I have termed a theory, which it correct, explains the dispersion of the inaterials in particles oi an order so minute as to be colloidal in size. By conditioning the material to be dispersed' (ag. asphalt), so that at a temperature not above the boiling temperature of iwater and above the freezing point oi Water, it is tacky and stringy, and then mixing therein a certain amount ot A water atfsubstantially the same temperature ot the mass (but not above the boiling point im of the water), the Water is4 absorbed by and distributed uniformly throughout the inass, so that the latter then consists ot minute particles of water dispersed in the asphalt. Then on introducing' into the mass on umrlfnnstnr', nnssscnusnrfrs, ns'sranion ro anesnonusnrrs-ja conronn'rron or a PROCESS OFQiDISERSNG -BQDmS IN Wel'EyE.

Lprocess by which these substances trom l0% to ld% -npp1nanon neanwemaeriaiaaa. .anni no. roanne.

4a colloidal agent, which will' iiirni, with the vWater a. stable protectivev it .1 ,w coating; about SAGHU- the articles of asphalt, the Vcontienne@ imm-, duction of Water intothe mass will' cause the separation of the colloid-protected particles and then' dispersion in the water.'

lin carrymg out theprocess it is neeeary that the body to be dispersed should be in a taclrystringy condition at a temperatnreabove the freezing point ot Water and below a point at which Water boils or is materially vaporized. Hence rt the body is liqnidat normal room temperature, it [should be chilled to al specllied con itionrvithin the temperature range stated, or, Aif itis normally solid at' normal room temperature, it should beheati int at which it reaches the ed to a point at which it has softened and may be manipulated in the mixer,-

l preterablyelnploy for manipulating the mass, i. e. pulling, stretching and stringing it, and incorporating the Water and the col loidalagent therein, a miner oi the general type o a Ross or lll'ernerv and Pdeiderer mixer, in which two rotary belinea or helically bladed rotors, operating .at diiierlen t peripheral speeds in close `prtnriniity Without touching, are caused to operate in a trough-like closed casing, interiorly shaped complementally to the rotors. The operative blades should not be operated at high speed, but at a speed :which results, pull. ing, Stringing, andrnixing the inass the manner oi3 a dough mixer. lhe casing shouldbe jacketed so that aheating or retrigerating medium may be through the jacket so as to bring the mass to be dispersed toand maintain it at'thev temperature at which the @mass is relatively sott, plastic and adhesive, and not in a liquid condition,

The mass having been placed in the mixer' and brought to the desired temperature necessary to condition that particular inass'orv manipulation, Water at substantially the saine temperature is fed gradually into the mixer while the blades are in operation.

caused to pass,

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'llhe amount of water necessary for the most 4effective and linestdispersion of the mass;

must he determined by trial, but it usually.'

ranges :from l0% to l5% ot the Weight ot' the body 'to be dispersed. en the Water has been completely absorbed, there is. now added to the mass and incorporated therein required amount of the dispesing or stabilizin colloidsl Preferably, though not necessari y, the colloid is mixed with water, to

\ stances as form a paste, or a gelatinous mass, depending of course, upon the articular colloid selected. Or if the colloid) is placed in the mixer in a dry form, thereis also gradually fed at the same time a stream of water. This 'is to supply sufficient Water to prevent too great absorption by the added colloid of the Water already in the mass and the disruption of the already formed colloidal particles of the body to be dispersed. `It is observable that as the mixing continues,

with the dispersion of the added colloid and' water throughout reached at which a the initial body in the mass, a point is change in phase occurs, colloid-protected partic es separating and constituting the disperse phase and the water the continuous phase of the disspersion.

Sometimes it is desirable to add to the water some agent to reduce the surface tension thereof and speed the change of phase and any such agent, which does not inhibit the dispersion may be employed, such for example as saponin or soapbark extract, or alkalis or alkali-acting bodies. I have used for this purpose very small roportions of caustic soda, caustic potash, orax, sodium silicate or the like.

I desire it to be understood that in the dispersion of various bodies immiscible with water, I may employ as the dispersig or stabilizing agent such colloids or' subcolloidal clay (including bentonite and Wilkenite), ultra line carbon black of colloidal size, glue, casein, Irish moss, agar-agar, blood albumen, bean albumen, or any other suitable colloid of animal, vegetable, or mineral origin.

The dispersion may be produced to have a-consistency similar, to that of salve orbutter, but by thel addition of Water, it may be diluted to practically any extent so as to have the consistency of thick or thin cream or milk, as may be desired. When in a relatively thick condition, like oil g or water paint, it may be spread with a brush Without gumming the brush, and if the colloidal dispersing agent has been properly selected and is not in excess, the dispersion may be formed in a filmvvhich on drying is not water absorbent.

By the process herein described I have successfully dispersed many bodies of Widely dilferent normal consistencies, such as paraffin, Ja an wax, Montan wax, dammar gum, non escript gum, asphalt (includin gilsonite) mineral rubbers, reclaimed rubber, rubber substitutes, wax tailings, vegetable oils and oxidized and sulphurized oils, and various compositions of matter including mixtures of said materials. Ifdea softening point not exceeding C. By l the application of heat, the mass is softened, and then when the mixer is set in operation an amount of Water at substantially the temperature of the asphalt and approximating 12% of the Weight ofthe asphalt, is fed graduall into the mixer. The latter is preferably provided with a cover which may be closed. As the mixer operates, the water is gradually absorbed andv entirely disappears in the mass, this occurring in about half an hour. The Water is not vlsible in the mass, but its absorption is accompanied by a corresponding increase in the bulk and weight of the mass. The mass is sticky and adhesive, and clings to the blades and to the interior surfaces of the mixer. I then add to the mass, a" paste or mud of the same temperature as the mass and consisting of'a suspension ofcolloidalclay in water, in the proportion of, say 4% by weight of dry clay tothe Weight of the asphalt.l This is homogeneously incorporated in the mass in about ten minutes and water is gradually added to the mass. After a perilod of about 20 minutes, a vchange takes p ace, ous phase. When this happens, the inner surfaces of the' mixer and the blades are observed to have been freed from any adhering asphalt and In the product thus produced, if the process has properlyV been carried on, the dispersed particles appear to be of uniform size, and

of an order of magnitude substantially no greater than`rubber globules in latex. The

are. substantially4 clean.'

apparent change of phase occurs, when or before the mass is of aboutI the consistency of cold cream, salve, or butter, but if the addition of water be continued, the dispersion may be increasingly diluted.

What I claim is:

l. -A process of dispersin which I in water bodies are immlscible Wit Water, which comprises causing any such body to absorb water by manipulating such body in the presence of vyater, and then mixing with the mass a dlspersing agentf'together with Water.

2l A process of dis ersin in water bodies which ,are immiscib e Wit water, which comprises causing any such body to absorb water to approximately the point of saturation, by manipulating such body in the presenceof water, andv then mixing with the which are immiscible with water, 'which 15 mass a dispersing agent together with wacomprises conditioning any such body to absorb Water during such conditioning and together with water, until the said body ter. v a tacky condition at a temperature above l 3. A process of dispersn in water bodies the freezing point of water and below the which are immiscible wit water, which ,boiling oint of water,'causing such body conlpicises conditioning any such'body to a to absor water in an amount substantiall 20 tacky condition at a temperature above the equal to theabsorption capacity of suc freezing point of water and below the boilbody during such conditioning, and then ing point of water, causing such body to mixing with said body va dispersing agent then mi ywith said body a dispersm rses in tbe water. agent toget erv with water, until the sai body dispersas in the water.

4. A process of dispersing in waterbodies testimony whereof I have aiixed my signature.

, WILLIAM BEACH PRATT. 

